A Reduced ‐ Graphene ‐ Oxide Entrapped CuCo ₂ S ₄ Nano‐Array for High‐performance Supercapacitor Electrode

Abstract

Abstract A low temperature and facile solvothermal method was used to synthesise CuCo 2 S 4 ‐ reduced Graphene Oxide (CuCo 2 S 4 ‐rGO) composite. Nearly uniform anchoring of rGO was achieved which could prevent the agglomeration of CuCo 2 S 4 effectively. Incorporation of CuCo 2 S 4 within the graphene network has effectively reduced the restacking of the nanolayers, increased its surface area and augmented the electrochemical performance of the composite. Supercapacitor electrode fabricated from this composite exhibit excellent electrochemical stability upto 5000 repeated galvanostatic charge discharge cycle. The calculated specific capacitance value, from galvanostatic charge discharge, for the electrode is 1090 F ⋅ g −1 at 1 A ⋅ g −1 . The material exhibits 992 F ⋅ g −1 specific capacitance even at elevated current density as high as 5 A ⋅ g −1 implying superior electrochemical stability. At 1 A ⋅ g −1 current density the material has energy density of 54.5 Wh ⋅ kg −1 with power density 543.94 W⋅kg −1 respectively. The electro‐kinetic study reveals that the material stores 69.35 % of total capacitance via capacitive controlled process.